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DefCon WiFi Distance Competition Calls For Entrants
Wireless Networking
Posted by timothy on Tue Jul 27, '04 05:30 AM
from the desert-shootout dept.
ASLRulz writes "The Adversarial Science Laboratory is running the Wi-Fi Shootout this year at DefCon and we are inviting people to come out and try to beat last years record of 35 miles. Register here. Hope to see you there."

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DefCon WiFi Distance Competition Calls For Entrants | Log in/Create an Account | Top | 74 comments | Search Discussion
The Fine Print: The following comments are owned by whoever posted them. We are not responsible for them in any way.
Homebrew (Score:3, Funny)
by Detritus (11846) on Tuesday July 27, @05:39AM (#9809452)
Now I know what to do with the surplus 20kW S-band klystron that I have sitting in the garage. All I need is a portable power supply.
  • Re:Homebrew by carnivore302 (Score:3) Tuesday July 27, @06:20AM
    • Re:Homebrew (Score:5, Informative)
      by pe1rxq (141710) on Tuesday July 27, @05:51AM (#9809471)
      A klystron is a type of vaccum tube used to generate microwave signals. Good ones can generate very powerfull signals (plenty-o-kilowatts)

      [ Parent ]
      • 1 reply beneath your current threshold.
      Re:Homebrew (Score:5, Informative)
      by Technician (215283) on Tuesday July 27, @06:07AM (#9809510)
      haven't the slightest clue what that mean,

      Do a Google search for klystron.

      You will find it's a vacuum tube. It has a cavity and is used like a magnitron to create microwaves. On most of them, the cavity contains metal bellows. This enables tuning it over a small range. Small ones were used for tuning the local oscillator in radar sets in the receiver. Tuning a 20,000 watt one to the WiFi band could not only disrupt the competition by jamming the band, but could overload and cook much of the low power stuff in the area.

      Maybe he wants to DOS the contest.

      To win the contest, he needs to establish a 2 way link. He can't win by blasting a one way signal.
      [ Parent ]
      • Re:Homebrew by WhiteDragon (Score:2) Tuesday July 27, @08:53AM
        • Re:Homebrew by JUSTONEMORELATTE (Score:2) Tuesday July 27, @09:51AM
          • Re:Homebrew by theLOUDroom (Score:2) Tuesday July 27, @06:41PM
          • Klystron wikipedia link by j1m+5n0w (Score:2) Tuesday July 27, @11:46AM
            • 2 replies beneath your current threshold.
            To be immediately followed by chinese food... (Score:3, Funny)
            by Ammishdave (688623) on Tuesday July 27, @05:47AM (#9809464)
            Now all the slashdotters will pull out their favorite cooking utensils [slashdot.org]
              Patriot Act (Score:1)
              by vi (editor) (791442) on Tuesday July 27, @05:51AM (#9809468)
              Don't you fear that the FBI will use the Patriot act to raid the conference ?
              wohooo! radiation! (Score:2, Funny)
              by tciny (783938) on Tuesday July 27, @05:54AM (#9809478)
              In other news: Attendees wont need to bring any cooking equipment.
              Wrap it up (Score:1)
              by smiley2billion (599641) on Tuesday July 27, @05:55AM (#9809479)
              Sweet Jesus, everyone invest in Reynolds Wrap [reynoldskitchens.com] now!
                I would (Score:2, Funny)
                by lachlan76 (770870) <lachlan76NO@SPAMhotmail.com> on Tuesday July 27, @06:00AM (#9809493)
                I'd enter, but I can't take off my tinfoil hat to use as a reflector.
                  Passive Relaying? (Score:5, Interesting)
                  by nacturation (646836) on Tuesday July 27, @06:02AM (#9809502)
                  I assume the "no active relaying" prohibition means that someone can't have waypoint stations to pick up and rebroadcast the signal to the destination. So this leaves the competition open to passive relaying.

                  How well does the 2.4GHz spectrum interfere with power lines? Would it be possible to put up a structure so that it modulates the power signal which is then decoded on the other end in a similar setup? At the very least, it might win a "Most Creative Bending of the Rules" award or something. :)
                  35 miles?! (Score:5, Funny)
                  by flopsy mopsalon (635863) on Tuesday July 27, @06:10AM (#9809514)
                  That must be one big-ass pringles container. They get that at Costco or something?
                  • Re:35 miles?! by InternationalCow (Score:2) Tuesday July 27, @06:29AM
                    56.3 km (Score:2)
                    by geirt (55254) on Tuesday July 27, @06:19AM (#9809527)
                    35 miles = 56.32704 kilometers [google.com]
                    • Re:56.3 km by Patrik_AKA_RedX (Score:2) Tuesday July 27, @07:50AM
                      • 1 reply beneath your current threshold.
                      Not necessarily power limited (Score:5, Interesting)
                      by elgatozorbas (783538) on Tuesday July 27, @06:30AM (#9809543)
                      Because WIFI operates in the microwave territory, you need a line of sight (LOS). These waves do not go 'around the bend', as e.g. long wave radio does. 'Around the bend' also implies 'around the Earth'. I can imagine that at some point the winners of this contest will no longer be limited by power, but by finding suitable high places to transmit and receive from.

                      Hams have the 10 Watt advantage!!! (Score:2)
                      by ivi (126837) on Tuesday July 27, @06:31AM (#9809544)
                      From my last visit to a retailer, I took away the suggestion that WiFi might be running on the order of 100 mWatts at GHz freq's.

                      Well, the new ICOM digital radios operate on 1.2 GHz with 10 Watts of transmit power.

                      Reviews suggest that mobile nodes can maintain
                      reliable links to other nodes while driving
                      around town.

                      Worth a look:


                      Oh, if you win, just earmark my 10% of your prize's $-value to me at... ;-)
                      • 1 reply beneath your current threshold.
                      Other records (Score:5, Informative)
                      by john_smith_45678 (607592) on Tuesday July 27, @06:34AM (#9809553)
                      (Last Journal: Tuesday August 10, @04:06PM)
                      A page to collect 'long shots' (sorted by distance). The goal is not (only) to break records, but also to get a feeling of what can be done with what.

                      * 82 miles, Utah, using parabolas and amplification (1500 mW) [WWW]Slashdot 10dec2003, [WWW]Rob Flickenger's blog, [WWW]experiment's site
                      * 116 km (72 miles), California, using parabolas and amplification ([WWW]Computer World, [WWW]HPWREN)
                      * 110 km in Poland ([WWW]Slashdot23sep2003), the [WWW]polish article (one of the [WWW]translations)
                      * 70.5 km, Spain, using parabolas ([WWW]CanariaWireless.net)
                      * 61.1 km, Downtown Seattle to MtBaldi using 24dBi parabolics, no amps (SeattleWireless)
                      * 35.2196 miles, Nevada, USA, using home built horn ([WWW]Defcon Wi-fi Shootout)
                      * 52km, Melbourne (Victoria, Australia) [WWW]http://melbourne.wireless.org.au using 25dBi grid pack to 180 degree slotted waveguide.
                      * 48 km, Perth (Western Australia), using a [WWW]satellite dish with biquad feed, connecting to a 180 degree waveguide
                      * 45.0 km, TacomaNode to MtBaldi using a 14.5dBi yagi and a 24dBi parabolic, no amps (SeattleWireless)
                      * 42.0 km, [WWW]Netherlands, SMC-Senao, 2 * 24 dBi dishes (SNR 17 dB)
                      * 36.4 km, Belgium, using a SlottedWaveguide, a [WWW]Yagi and a parabola ([WWW]Florenville-Arlon)
                      * 33.7 km (20.9 miles), California, using parabolas ([WWW]Oreilly)
                      * 26.4 km , Perth (UK) using 10 dBi omni + Parabola 24 dBi (http://www.consume.net/mhonarc/thenet/msg02844.ht ml)
                      * 24 km, Lausanne/Switzerland, using 2 Paraolic 24 dBi by [WWW]Submusic Team [WWW]photos and explications (in french)
                      * 10 miles (TestingTenMileLink)
                      * 15 km, Belgium, using a SlottedWaveguide and a CardboardHorn ([WWW]LouvainWaterloo)
                      * 9.5 km, Belgium, using 2 CardboardHorn ([WWW]Liege20020615)
                      * 5 km, Belgium using DirectionalWaveguide (tin cans), ([WWW]Liege20020401)
                      * 3.5 km, Belgium, using 2 unmodified LinksysWET11
                      http://www.seattlewireless.net/index.cgi/LongShots [seattlewireless.net]
                      Last Year's Record (Score:1)
                      by john_smith_45678 (607592) on Tuesday July 27, @06:36AM (#9809557)
                      (Last Journal: Tuesday August 10, @04:06PM)
                      Last year's record is mentioned in this article:

                      Wi-Fi Fidelity
                      Wireless technology opens up a world of possibilities—and a can of worms
                      http://www.meetingsfocus.com/displayarticle.asp?id =2483 [meetingsfocus.com]
                        Wifi shootout... (Score:2)
                        by dj245 (732906) on Tuesday July 27, @07:08AM (#9809616)
                        ...Where the range of your unprotected wireless network is longer than the range of the gun you use to chase people away from it.
                        Or Not? (Score:3, Funny)
                        by IcEMaN252 (579647) on Tuesday July 27, @07:26AM (#9809656)
                        Hope to see you there.
                        You won't see me, I'll be too far away.
                          I think I can win this.... (Score:2, Funny)
                          by dave-tx (684169) on Tuesday July 27, @07:32AM (#9809679)
                          Finally, a perfect application for my 40-mile-long wifi antenna... made out out of cat-5 cable.

                          What would really impress me wouldn't be 35 miles (Score:3, Interesting)
                          by usurper_ii (306966) on Tuesday July 27, @07:49AM (#9809719)
                          line of sight, it would be a three to five mile radius working through trees...and even hills. Now someone pulling that off cheaply and legally would be like pulling Excalibur out of its rock and it would impress the hell out of me. (by the way, I'm involved in a wireless ISP that is getting hammered by the local terrain).


                          So if (Score:1)
                          by kc0re (739168) on Tuesday July 27, @09:00AM (#9810173)
                          (Last Journal: Tuesday February 10, @04:45PM)
                          So if people can go to these competitions and shoot 35 miles, can someone come to my house and see why my lappy won't work on my back porch. K-Thanks.
                            Curvature of the Frigging Earth (Score:2, Informative)
                            by bugmenot (788326) on Tuesday July 27, @10:17AM (#9810996)
                            (Last Journal: Saturday July 31, @05:16AM)
                            The horizon is about 35 miles away. If you get much further than that you are in an airplane.
                            35 miles? (Score:1)
                            by Kvasio (127200) on Tuesday July 27, @10:34AM (#9811218)
                            http://it.slashdot.org/article.pl?sid=03/09/23/123 3219&tid=193 [slashdot.org]
                              As if I needed another excuse to say.... (Score:1)
                              by asink (106056) on Tuesday July 27, @10:39AM (#9811273)
                              Mine is longer than yours.

                              Yes, I am actually going again this year, so this is a joke.(or so you think....)
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